Baby measuring small, should I be worried?

Gwen • 32. Wife. Mom to Harper 8.21.17 {10 weeks premature} & our 🌈 baby, Emerson 10.11.22. Currently pregnant with our 3rd and final baby, due 1.30.25. Pre-eclampsia and Postpartum Hemorrhage survivor. Miscarriage 2.17.21 {12 weeks 5 days}.
I'm a FTM and at my 8 week and 12 week ultrasounds my baby girl was measuring right on track or even a day ahead of where she should be size wise. But by the 20 week appointment she had fallen behind and was measuring about a week smaller than she should be.
I'm currently 22 weeks and have yet to feel any kind of movement from her. 
I'm worried something is wrong and she's not getting big and strong like she needs to be. 
Has anyone had this happen and everything turn out fine? Should I be concerned that she's not the size she should be right now? Should I request an ultrasound (not a regularly scheduled one) at my 24 week appointment to check on her?